Some form of display products is used in just about every imaginable field of human endeavor. Any application in which information of some form or another is to be conveyed will most probably use one or more display products to convey that information. Display products, which include screens, monitors, such as computer and video monitors, and projectors, are indispensable to engineering, scientific, educational, government, military, and entertainment endeavors.
A common problem with displays is that an image will burn into the display after the image has been static or unchanging for a long period of time. Cathode ray tube (CRT), plasma, and liquid crystal display (LCD) displays are well known examples of display products that are susceptible to the burn-in problem. Of course, the longer a static image is displayed, the greater the probability that burn-in will result. Burn-in of the image results in an objectionable pattern that becomes visible when the product display changes to another image. Burn-in of an image in expensive display products, such as costly video monitors and projectors, is of particular concern. For example, in cases where large numbers of video communications links are continuously monitored, it is common that one or more display products will brightly display the same, unchanging image, such as logos, test patterns, or color bars, for long periods of time.
The display burn-in problem has typically been addressed with so-called "screen-saver" software, especially in the realm of computer screens. Screen-saver software detects a lack of input from the user interface and, after a predetermined time, usually set by the user, the software will invoke screen-saving activity that prevents burning of the image in the display product. The use of such screen-saving software is well known in the field and is available both commercially and at no charge.
While the software screen-savers commonly used for inexpensive display products, such as computer monitors, operate to prevent burning of the image into the display, they by definition do not permit the image to been seen on the display product once invoked. There are many applications, particularly where expensive display products are used, where it is desirable for the image to be continuously displayed on a display product. High-end video monitors and screens, for instance, are used to display advertisements that do not change for long periods of time in high visibility areas like airports and shopping malls. Where advertisers pay top dollar in order to purchase such prime advertising locations, the advertising image must be continuously displayed. A display product in which a company logo has been burned into the display often must have its CRT replaced, even though the display product may otherwise be functioning properly. Or, consider a broadcast monitor used in a security office of a jail or a secured military environment that must display the image of a remote location under surveillance for indefinite periods of time. In all of these applications, the image must be shown indefinitely regardless of the possibility of image burn-in.
In light of the above discussion, it is clear that there exists a need in the art to be able to indefinitely display an image on a display product while preventing burn-in of the image.